1. Field of the Invention
The present invention relates particularly, though not solely, to the delivery of humidified pressurised oxygen and/or air to a patient. In particular, the present invention relates to connections used to couple heated breathing conduits together.
2. Summary of the Prior Art
In order to supply gases to a patient or a person needing such gases, it may sometimes be necessary to first humidify those gases, for example using a respiratory humidifier/ventilator system. In such a case where the gases have been humidified, and therefore laden with water, it is likely that during transport through a conduit to the patient, condensation of that water vapour will occur. In order to overcome this disadvantage it is known to associate a heater wire with respiratory humidifier breathing conduits to avoid condensation. Examples of such a heated breathing conduit are disclosed in U.S. Pat. No. 5,537,996 (McPhee) and U.S. Pat. No. 5,392,770 (Clawson et al.).
A piece of soft extremely flexible connecting tube is commonly used at the end of a heated respiratory conduit to connect to a mask or mouthpiece. The breathing circuit, while flexible, will necessarily be stiff enough to maintain its integrity over comparatively long runs, while the connecting tube, being only a short length, for example 10 centimetres, merely has to span between the user's mouth and chest, and can thereby be made in a manner that would not be suitable for long runs. It has been found that condensation may form in the short flexible connecting tube causing problems to the patient.